In an evolved packet system (Evolved Packet System, EPS), service data of user equipment (User Equipment, UE) is transmitted by using a bearer (Bearer), and in accordance with different networks passing by service data in a bearer, a Bearer includes two types, namely, a core network (Core Network, CN) bearer and a radio access network (Radio Access Network, RAN) bearer.
In an existing radio network, for a particular service, an RAN bearer may adopt two transmission modes in a radio link control (Radio Link Control, RLC) layer, i.e., an acknowledged mode (Acknowledged Mode, AM) and an un-acknowledged mode (Un-acknowledged mode, UM). In an AM mode, an RLC layer transmits service data by adopting an automatic repeat-request (Automatic Repeat-reQuest, ARQ) mechanism, and a receiving end acknowledges each data packet sent by the sending end, so as to indicate that the data packet is received correctly. The AM mode is applicable to a service transmission requiring relatively low latency and relatively high reliability. In an UM mode, an RLC layer is only responsible for sending and receiving a data packet, and does not retransmit a sent data packet and feed back acknowledgment regarding a received data packet. Compared with the AM mode, the UM mode is mainly applicable to a service requiring higher latency and lower reliability.
The prior art has at least following shortcoming, namely, in a transmission mode adopted by an existing radio network, either for a CN bearer or an RAN bearer, or in an AM mode or a UM mode of an RAN bearer, data packets corresponding to different types of service data in a service are processed intensively, resulting in low processing efficiency of a data packet.